<?php
    /**
    * Global Search Engine for Moodle
    *
    * @package search
    * @category core
    * @subpackage search_engine
    * @author Michael Champanis (mchampan) [cynnical@gmail.com], Valery Fremaux [valery.fremaux@club-internet.fr] > 1.8
    * @date 2008/03/31
    * @version prepared for 2.0
    * @license http://www.gnu.org/copyleft/gpl.html GNU Public License
    *
    * Asynchronous adder for new indexable contents
    *
    * Major chages in this review is passing the xxxx_db_names return to
    * multiple arity to handle multiple document types modules
    * 
    * changes are in implementing new $DB access
    */

    /**
    * includes and requires
    */
    require_once('../config.php');

    if (!defined('MOODLE_INTERNAL')) {
        die('Direct access to this script is forbidden.');    ///  It must be included from the cron script
    }

    global $DB;

/// makes inclusions of the Zend Engine more reliable
    ini_set('include_path', $CFG->dirroot.DIRECTORY_SEPARATOR.'search'.PATH_SEPARATOR.ini_get('include_path'));

    require_once($CFG->dirroot.'/search/lib.php');
    require_once($CFG->dirroot.'/search/indexlib.php');


/// checks global search activation

    // require_login();

    if (empty($CFG->enableglobalsearch)) {
        print_error('globalsearchdisabled', 'search');
    }

    /*
    Obsolete with the MOODLE INTERNAL check
    if (!has_capability('moodle/site:doanything', get_context_instance(CONTEXT_SYSTEM))) {
        print_error('beadmin', 'search', get_login_url());
    }
    */

/// check index

    try {
        $index = new Zend_Search_Lucene(SEARCH_INDEX_PATH);
    } catch(LuceneException $e) {
        mtrace("Could not construct a valid index. Maybe the first indexation was never made, or files might be corrupted. Run complete indexation again.");
        return;
    }
    $dbcontrol = new IndexDBControl();
    $addition_count = 0;
    $startindextime = time();

    $indexdate = @$CFG->search_indexer_run_date;

    mtrace('Starting index update (additions)...');
    mtrace('Index size before: '.$CFG->search_index_size."\n");

/// get all modules
    if ($mods = search_collect_searchables(false, true)){

/// append virtual modules onto array

        foreach ($mods as $mod) {
            //build include file and function names
            $class_file = $CFG->dirroot.'/search/documents/'.$mod->name.'_document.php';
            $db_names_function = $mod->name.'_db_names';
            $get_document_function = $mod->name.'_single_document';
            $get_newrecords_function = $mod->name.'_new_records';
            $additions = array();

            if (file_exists($class_file)) {
                require_once($class_file);

                //if both required functions exist
                if (function_exists($db_names_function) and function_exists($get_document_function)) {
                    mtrace("Checking $mod->name module for additions.");
                    $valuesArray = $db_names_function();
                    if ($valuesArray){
                        foreach($valuesArray as $values){
                            $where = (isset($values[5])) ? 'AND ('.$values[5].')' : '';
                            $itemtypes = ($values[4] != '*' && $values[4] != 'any') ? " AND itemtype = '{$values[4]}' " : '' ;

                            //select records in MODULE table, but not in SEARCH_DATABASE_TABLE
                            $table = SEARCH_DATABASE_TABLE;
                            $query = "
                                SELECT
                                    docid,
                                    itemtype
                                FROM
                                    {{$table}}
                                WHERE
                                    doctype = ?
                                    $itemtypes
                            ";
                            $docIds = $DB->get_records_sql_menu($query, array($mod->name));

                            if (!empty($docIds)){
                                list($usql, $params) = $DB->get_in_or_equal(array_keys('$docIds'), SQL_PARAMS_QM, 'param0000', false); // negative IN
                                $query =  "
                                    SELECT id,
                                        $values[0] as docid
                                    FROM
                                        {{$values[1]}}
                                    WHERE
                                        id $uslq AND
                                        $values[2] > $indexdate
                                        $where
                                ";
                                $records = $DB->get_records_sql($query, $params);
                            } else {
                                $records = array();
                            }

                            // foreach record, build a module specific search document using the get_document function
                            if (is_array($records)) {
                                foreach($records as $record) {
                                    $add = $get_document_function($record->docid, $values[4]);
                                    // some documents may not be indexable
                                    if ($add)
                                        $additions[] = $add;
                                }
                            }
                        }

                        // foreach document, add it to the index and database table
                        foreach ($additions as $add) {
                            ++$addition_count;

                            // object to insert into db
                            $dbid = $dbcontrol->addDocument($add);

                            // synchronise db with index
                            $add->addField(Zend_Search_Lucene_Field::Keyword('dbid', $dbid));

                            mtrace("  Add: $add->title (database id = $add->dbid, moodle instance id = $add->docid)");

                            $index->addDocument($add);
                        }
                    }
                    else{
                        mtrace("No types to add.\n");
                    }
                    mtrace("Finished $mod->name.\n");
                }
            }
        }
    }

/// commit changes

    $index->commit();

/// update index date and size

    set_config('search_indexer_run_date', $startindextime);
    set_config('search_index_size', (int)$CFG->search_index_size + (int)$addition_count);

/// print some additional info

    mtrace("Added $addition_count documents.");
    mtrace('Index size after: '.$index->count());

?>
